Proton beam therapy can potentially offer improved treatment for cancers of the head and neck and in paediatric patients. There has been a sharp uptake of proton beam therapy in recent years as improved delivery techniques and patient benefits are observed. However, treatments are currently planned using conventional x-ray CT images due to the absence of devices able to perform high quality proton computed tomography (pCT) under realistic clinical conditions. A novel approach aiming to develop a full pCT system using the most advanced particle physics and techniques is presented here. Silicon pixel trackers are used to track the protons before and after the imaged body while a new plastic-scintillator-based range telescope concept, named ASTRA , is proposed here to measure the proton’s energy loss. Simulations conducted using GEANT4 yield an expected energy resolution of 0.7 . If calorimetric information is used the energy resolution could be further improved to about 0.5 . In addition, the ability of ASTRA to track multiple protons simultaneously is presented. Due to its fast components, ASTRA is expected to reach unprecedented data collection rates, similar to 108 protons/s. The performance of ASTRA has also been tested by simulating the imaging of phantoms. The results show excellent image contrast and relative stopping power reconstruction. Further analysis of the ASTRA range telescope data using calorimetric in formation and deep neural networks showed an increase the efficiency of the detector on multi-proton events by a 23 % with the potential to reduce the dose received by the patient during the imaging process.